Gas switch



July 23,A 1935. G. Hl-:GWEIN Er AL 2,009,193

GAS SWITCH Filed July 28, 1933` 4 Sheets-Sheet 1 34 ze so 25 58 6 F rwen'or's July 23, 1935. G, HEGwEm Er AL 2,009,193

.GAS SWITCH Filed July 28, 1935 4 Sheets-Sheet 2 July 23, 1935. G. HEGWEIN Erm. 2,009,193

GAS SWITCH Filed July 28, 1955 4 Sheets-Sheet 3 July 23, 1935. G. HEGwElN Er n.

GAS SWITCH Filed July 28, 1933 4 Sheets-Sheet 4 Y 'duly ""Mornegs Patented July 23, 1.935

- UNITED STATES PATENT OFFICE annales GAS swrrcn Application July 28, 1933, Serial No. 682,716

In Germany August 1, 1932 23 Claims. (Cl. 236-25) The present invention relates to gas valves, and more especially to gas valves incorporating a working part such as a diaphragm, bell, piston or the like which is operated by variations of pressure produced in the controlling chamber of the gas valve by an auxiliary gas current, in the path of which controlling valves are arranged which operate in response to the Working conditions to be controlled, for instance temperature, pressure, current Velocity, height of liquid and so forth. The invention comprises a controlling device operating in response to pressure changes in the consumption pipe, for example, the feed pipe to a burner, or in response to pressure changes in the gas supply pipe whereby the auxiliary current of gas, besides controlling the feed of gas to the burner in dependence on the working conditions to be controlled, also enables the pressure or the quantity of the gas lcurrent allowed to pass to the burner to be kept constant.

Several examples of construction of the invention are shown inthe accompanying drawings, in which:-

Figurel is a view, partly in side elevation and partly in 'section and largely diagrammatic of a gas valve with a pressure-control arrangement according to the invention.

Figure 2 is a similar View of a gas valve embodying a control device of somewhat diierent form and mode of operation from that of Fig. 1 but also coming Within the present invention.

Figure 3 is a vertical section through a gas valve having a control device or arrangement like that of Fig. 2 but modified in certain mechanical details.

'Figure 4 is a plan view of the gas valve shown in Fig. 3 with the casing 'cover removed.

Fig. 5 is a vertical sectional view of a gas valve videntical withthat shown in Fig. 3 except for a modification in the means provided for adjusting the control device.

Fig. 6 is a partial vertical sectional View of the valve shown in Fig. 3 but with a further modification in the said adjusting means.

Fig. 7 is a partial vertical sectional view of the valve shown in Fig. 3 but with al still further modiction in' the said adjusting means.

tributor chamber I 8.

gas entering at I0 into a, burner pipe II leading to a main burner B. 'I'he valve, denoted generally at A, comprises a casing Within which is located the main valve I2, secured to the diaphragm I3, which diaphragm bounds, on the one side, the main pressure chamber I4, and on the other side, the control chamber I5 of the valve casing, and in which latter chamber a closing spring I6 is arranged. The diaphragm I3 is operated by differences in pressure which are produced in the control chamber I5 by the opening and closing of a current of control gas. The current of control gas is derived from the main pressure chamber I4, and flows through a passage I1 first into a dis- The distributor chamber is in .permanent communication by a narrow throttle I 9 with a control pipe 20, whose outlet 2| is controlled by a, thermostatic valve 22 inuenced by the pilot flame, which valve is connected with a heat-sensitive expansible diaphragm 23 of a safety pilot burner C. The narrow throttle I9 limits the strength of the current of gas, which is necessary for the permanent maintenance of the pilot flame. Further, the distributor chamber is in permanent Acommunication with the control chamber I5 by a Wide throttle 24, which limits the greatest amount of control gas which can ilow to the control chamber I5-. The control chamber I5 is closed by a partition wall 50 in which an aperture 5I is provided, controlled by a controlling valve 52. The opening 5| connects the control chamber I5 with a chamber 53, through the wall 54 of which the rod 55 of the controlling valve 52 is carried in a gas-tight manner and is connected with the controlling diaphragm 56 of a pressure-controller F, the pressure chamber 51 of which is connected by a passage 58 with the outlet Il of the gas valve A. The respiratory chamber 59 of the pressure controller F is closed by a cover 60 having an opening 6I.

If the consumption pressure rises in the valve outlet II, this increase in pressure is transmitted through the passage 58 to the chamber 51 of the pressure controller and presses the controlling diaphragm 56 downwards against the action of a loading spring 62, so that the controlling valve 52 is more or less closed. Consequently the current of control gas owing through the passage I1, distributor chamber I8 and the wide throttle 24 into the control chamber I5 accumulates and causes the valve diaphragm I 3 to rise and somewhat close the main valve I2, whereby the pressure in the consumption pipe II is again reduced to the adjusted maximum value.

The current of control gas passed by the controlling valve 5|, 52 of the pressure controller F ows from the chamber 53 through a passage 25, which opens into a valve chamber 26 of a controller D which responds to variations of any working conditions to be controlled. The controller D might, for example, be a thermostatic valve which responds to the heat of a room or a liquid; it might also be a water-level controller or a steam-pressure controller. The example of construction illustrated shows the gas valve employed in connection with a water-heater or geyser and the controller D comprises a vane or valve operated by the current of water. In the valve chamber 26 of this controller D a controlling valve 21 is arranged. which controls the outlet 28 of the chamber 26 in the control gas pipe 20 and is connected to a lever 29, which is rockably vmounted in a diaphragm 30.

The diaphragm 30 forms at the same time a closure for the chamber 3| on the gas side, in which one arm of the rocking lever 29 is situated, against a chamber 32 traversed by the water. into which the other arm of the lever 29 carrying a disc 33 projects. The water chamber 32 is connected, on the one hand, to a water supply pipe 34, and on the other hand to a water pipe 35 leading to the heater E, the outlet of which is controlled by one or more cocks Z.

So long as water is not flowing, the control valve 21. is closed by the overbala'ncing weight of the disc 33. 'Ihe control gas can thus ilow outwardly from the distributor chamber I8 only through the narrow throttle I9, 'whilst the admission of the control gas through the passage I1 takes place almost unthrottled. Consequently, there prevails in the distributor chamber I8 almost the main gas pressure, which is transmitted through the wide throttle 24 to the control chamber |5, so that the same pressure prevails on both sides of the diaphragm I3 and the spring I6 holds the valve member I2 of the main Agas valve A closed. If, on the other hand the cock Z is opened, the owing water striking on the disc 33 rqpks ,the lever `29 and opens the control gas valve 21 of the water current controller D. Consequently, the control gas. which is inthe chamber I5 can ow away unthrottled through the open valve 52, chamber 53, duct 25, chamber 26, and outlet 28 to the control pipe 20, whilst the control gas flowing from the distributor chamber I8 through the throttle 24 is throttled, so that a fall in pressure takes place in the control chamber I'5. This fall in pressure effects the opening of the main valve I2, so that now the gas iiows to the burner B, where it is ignited by the pilot flame of the pilot burner C. The pressure controller F then causes the pressure in the burner pipe II to be kept uniform.

If the pilot ame at the safety pilot burner C goes out for any reason the thermostatlc valve 22, 23 closes the outlet of the control gas pipe 20 so that the pressure in the control pipes and in the control chamber I5 rising to the main pressure causes the closing of the main valve I2.

. The current of control gas thus serves for controlling the main valve in dependence on the safety device C and the water controller D as well as for regulating the consumption pressure ofthe gas in the outlet pipe I leading to the burner.

From the distributor chamber I8 an ignition pipe 63 also leads to the pilot burner C, and serves for by-passing the thermostatic valve 22 and is' controlled by manually operated ignition valve 64.

`the higher pressure.

In Figures 2-9 a gas valve is shown, in which the quantity of gas passing through in a unit of time is kept constant instead of the pressure in the outlet pipe of the valve.

In the diagrammatic drawing (Fig. 2), A again generally designates the gas valve, which controls the flow of the main gas from the main supply 4 wall |10, which cooperates with the diaphragm ||3 to separate off a control chamber I1| in front of or above the diaphragm and through which passes a valve-rod |12 connecting the main valve 2 with the diaphragm ||3, and of a hood |13 which cooperates with the diaphragm to separate on a controlling pressure chamber I|5 from an ante-chamber |14 formed by the hood and the lower part 300 of the outer casing of the valve. The hood |13 is formed with a non-return valve casing |15 in its lower wall, which contains a non-return valve |18 having a throttle so controlling |19, said valve opening a passage |16 in the bottom of the valve casing as to open the passage when there is excess pressure in the antechamber |14 and closing under the action of a spring |11 on a fall in pressure in the ante-chamber |14. This non-return valve serves for lnuencing the speed of operation of the gas valve, in that by opening the passage |16 it allows any rise in pressure in the ante-chamber I1.4 to quickly enter the controlling chamber I5, so that the diaphragm ||3 rapidly closes the main valve |I2, whilst on a fall in pressure in the ante-chamber |14 it closes the passage |16, and allows the controlling pressure acting on the valve diaphragm II3 to escape only slowly through the throttle opening |19, so that the main valve I I2 only slowly opens.

The partition wall |10 carries a cup |80, which closely surrounds the outlet I I I, so that the seat of the main valve ||2 and the main valve ||2 with its closing spring II6 are situated within the intermediate pressure chamber |8| enclosed by tle cup and the partition wall |10. The wall of the cup |80 is provided with openings |82, which can be more or less opened or closed by means of a sliding valve |83 or the like. These openings |82 by their throttling action enable a difference in pressure to be produced between the high pressure in the main pressure chamber I4 and the intermediate pressure in the chamber |8| within the cup |80. This difference of pressure is used to operate a controlling member which controls the control gas pressure acting on the diaphragm II3. For this purpose, an opening |84 is provided in the cup |80 leading into a chamber |85, in which a pressure-sensitive controlling member, which may be a diaphragm, piston, bell, float or the like, but in the present instance is a controlling disc |86, is so arranged that the main pressure prevailing in the main pressure chamber ||4 acts on one side of it, and on its other side the intermediate pressure in the chamber |8I. The controlling disc so slidingly fits the chamber |85 that the disc is'moved by the difference between these two pressures. A spring |81 opposes The controlling disc |86 is so arranged that it governs the inlet to a passage |88 which leads from the intermediate pressure chamber |8| into the controlling pressure chamber 1| in front of (above) the valve-operating diaphragm I|3.

5 The current of control gas flowing from the intermediate pressure chamber I8| through the passage |88 into the controlling chamber I1| in front of or above the diaphragm 3 passes through a passage ||1 into a distributor chamber l0 ||8, which is in constant communication by a narrow throttle ||9 with a control gas pipe |20 terminating in a thermostatic safety. pilot burner C, whose function is the same as that of the pilot burner C described with reference to Fig. 1. A

second but wide throttle |24 connects the distributor chamber with a passage |25, which leads at one side into the ante-chamber |14 behind or below the diaphragm I|3 and on the other side into the valve chamber |26 of a controller D. For

the sake vof simplicity, the control arrangement is again shown in the same way as in Fig, l, so that it is needless to describe it.

The mode of working of the gas valve shown in Fig. 2 is as follows:-

When no water is flowing through the pipe |34, |35, the controlling valve |21 remains closed. The control gas flows from the intermediate pressure chamber I8I through the passage |88 into the control chamber above the diaphragm 30 I I3 and then passes from the chamber |1| through the passage ||1, distributor chamber ||8 and the wide throttle |24 to the passage |25 and from there into the ante-chamber |14. The non-return valve |18 opens and allows the control gas 55 to enter the chamber II 5 directly behind the diaphragm II3. Substantially the same pressure now prevails on both sides of the diaphragm I I3, and therefore the force of the closing spring ||6 can press the valve plate ||2 on to its seat. A

l0 very small .quantity of gas ows continuously through the narrow throttle ||9 to the pilot burner C and there maintains a pilot llame.

' `When the controlling valve |21 is opened by the pressure of the flowing water, thegas escapes ,5 from the ante-chamber |14 very rapidly through the unthrottled outlet |28 into the control gaspipe |20. On the other hand, the control gas enclosed in the control chamber I I5 can flow only slowly through the ne opening |19 in the non- 0 return valve |28 into the ante-chamber |14. As the throttle |24 is narrower than the outlet |28 of the control pipe |20 and only allows the passage of a limited quantity of control gas, there arises in the ante-chamber 14 and in the con- 5 trol chamber 5 behind the diaphragm ||3 a drop in pressure relative to the pressure of the gas in the control chamber I1| on the front side of the diaphragm, which effects the opening of the valve I |2. The opening is however completed D only slowly, because the non-return' valve |18 closes, and the passage of the gas from the control chamber ||5 to the ante-chamber |14 is possible only through the ne opening |19. The gas coming from the main gas-pipe I I 0 flows through the ippening |82 in the partition wall |80 before it passes into the burner pipe I||. The effective cross-section of the gas-passage is adjusted by the slide or valve |83 corresponding to the gas consumption of the main burner B. If the gas con'- sumption of a burner is small, the openings |82 in the wall |80 are suitably closed by moving the valve I 83; if the gas consumption of the apparatus for which the gas controlling valve is intended is large, the openings |82 are further opened. This adjustment corresponds, however,

only for a given pressure of the gas mains. In order even where the mains pressure is variable, to enable a uniform quantity of gas to be constantly supplied to the burner B, the valve plate I I2 must narrow the gas passage when the mains pressure is higher and enlarge it when the mains pressure is smaller. The controlling disc |86 is employed for this purpose. A fall in pressure occurring in the gas current through the valve casing between the main pressure chamber I4 and the chamber I8| enclosed by the partition wall I 80, influences the controlling disc |86 and thus the current of control gas which iiows through the opening |88. If the mains pressure increases, the controlling disc |88 is forced towards the opening |88. away through the passage ||1, the pressure is reduced in the control chamber |1| directly above or in front of the diaphragm ||3. Consequently, the valve plate ||2, under the inuence of the spring ||6, can now execute a closing movement, and the cross-section of the gas passage is reduced. If the pressure difference between the chambers ||4 and |8I is reduced to a value equal to or less than the force of the spring |81, the controlling disc |86 is brought by the spring |81 again into the initial position. The throttling action thus ceases and the pressure in the control chamber |1| above the diaphragm ||3 again increases, so that the gas control valve I2 is correspondingly further opened. The varying pressure of the mains is thus regulated by the controlling disc |86 automatically for the passage of a constant quantity.

In the gas valve according to Figs. 3 and 4, the upper boundary wall |80 of the diaphragm capsule |10, |13 is provided with sector-shaped recesses |89 which open towards the intermediate pressure chamber 8| and are closed at top by the revoluble adjusting valve ring 83. The adjusting valve ring |83 corresponds at the same time to the partition Wall |80 of Fig. 2, as it separates the main pressure chamber ||4 from the intermediate pressure chamber |8I. It is pro,- vided with a scale |90 according to which the adjustment for the desired gas quantity takes As the control gas further iiows place. The adjustment of the valve ring |83 is eii'ected by rotation about the axis of the gas valve, it being guided by wall parts I9 I. A screw |92 Iserves for clamping the valve ring |83 in adjusted position. The openings |82 are so arranged in the valve ring 83, and of such shape,

that in dividing the scale into equal parts each rotation of the valve ring byl one division always corresponds to a variation of the gas quantity by the same amount. 'I'he controlling disc |86 of the controller for the gas quantity is mouunted in a cup-shaped casing or capsule |93 screwed into the boundary wall |10. A sieve |94 retains any impurities in the gas above the'main valve ||2; furthermore, in front of the controlling disc |88` a line-mesh sieve |95 is also arranged and connected with the controlling capsule |93, and prevents even the vfinest impurities from reaching the controlling disc |86.

Figs. 5-7 show devices operable from the outside for the adjustment of the valve ring |83, so that the casing of the gas valve need not be opened up for adjustment of the quantity of gas. For this purpose, the.valve ring |83 in Fig. 5 is provided with a toothed portion |96, in which engages a toothed wheel |98 on a small shaft |91. 'I'he toothed wheel |98 can be rotated, as required, by means of the head |99 provided with can be adjusted.

The arrangement according to Fig. 6 differs from that in Fig. 5 only by the fact that the shaft |91l of the pinion |98 lis separate from the adjusting knob |99, which is only inserted like a key or spanner when an adjustment is to be made. The adjusting gear wheel |98 is of such smaller diameter than the shaft |91, that the shaft |91 with the gear wheel |98, can be entirely removed after y the adjustment is made, and the opening of the passage for the shaft bearing closed by a plug. By this means an unauthorized adjustment of the valve, ring |83 is obviated. According to Fig. 7 by adjusting a screw 200, a plate 20| can be moved relatively to an additional passage 202 leading laterally from the main pressure chamber ||4 to the intermediate pressure chamber |8|, and the said passage is thereby more or less opened, whereby the quantity 01 gas owing through the valve and the difference in pressure prevailing on the controlling disc |86 are varied. The screw. 20|!v is accessible I.irom the outside by an opening 203 which can be closed. The controlling disc capsule consists according to Figs. 8 and 9 of a cup-shaped casing or capsule |93, which is provided with a eaded stem 204, and a cover 205 in which t sieve |95 is clamped. The cover 205 has openings 206 for the passage of the gas from the main pressure chamber H4, whilst the bottom of the capsule |93 has openings 201 for the entrance of the gas from the intermediate pressure chamber |8|. The controlling disc |86 is inserted so as to lie free in thecapsule v |93, 205. The controlling spring |81 is introduced into an annular recess 208 in the stem 204. 'I'he disc |86 is provided with projections 209, to ensure that the disc\\ does not bear with its whole.

surface, but only at points, against the walls of the capsule. By this means any sticking of the disc is prevented. The capsule |93 with its contained parts of the Fig. 8 construction is a modi'- cation of the capsule |93 and its contained parts of the Fig. 3 construction and is intended to be mounted in one of the recesses |89- of the intermediate-pressure chamber |8| as shown for the capsule |93 in the Fig. 3 construction and the passage |88 through-the stem oi the capsule |93 of Fig. 8 forms the inlet for the controlling gas from theintermediate-pressure chamber |8| t0 the control pressure chamber |1| in front of or above the diaphragm ||3 (see Fig. 2). If the difference in pressure on the opposite sides of the disc |86 is smaller .than the force of thespring |81, the disc is raised 'from its seat 2|0 bythe spring |81, and the control gas from the intermediate pressure chamber |8| can pass through the openings 201 into the capsule |93 beneath the disc |86 therein and therefrom through the passage |88 into the control chamber |1| directly above the diaphragm ||3. If the diierence in pressure is greater than the force of the spring. the current of control gas is throttled by the controlling disc |86 which is moved against the valveseat 2|0. In order thatthe unavoidable inexactitudes in manufacture of the controlling de- -vices may be compensated for, a pivoted valve plate 2 is provided in the cover of the capsule |93 above the openings 206, and by turning this pivoted valv'e plate the width of passage of the openings 206 and thus the fall in pressure can be varied.

We declare, that what we claim is:

A1. A diaphragm-operated gas valve comprising a main casing having a gas inlet and a gas outlet at one end thereof, a main division plate in said casing having a control passage therethrough, a main diaphragm on the side of said division plate opposite said gas inlet and gas outlet, a main valve on the other side of said division plate controlling said outlet, a connection between the diaphragm and the valve, a shroud enclosing said main valve and the outlet opening and having a valve-controlled opening therein, a valve member within said shroud and subject tothe pressures on opposite sides of the shroud for controlling said control passage and for influencing the diaphragm to maintain substantially constant the volumetric flowthrough said outlet and a conftroller subject to external working conditions con- `nected with opposite sides of said main diaphragm'.

2. A diaphragm-operated gas valve comprising Aa casing having a gas inlet and a gas outlet at one end thereof, a main division plate in said casing having a control passage therethrough, a main diaphragm on the side of said division plate opposite said gas inlet and gas outlet, a main valve on the other side of said division plate controlling said outlet, a connection between the diaphragm and the valve, a shroud enclosing said main valve and the outlet opening and having a controllable opening therein, a valve member consisting of a thin disc within said shroud and subject to the pressures on opposite sides of the shroud for controlling said control passage and for influencing the diaphragm to maintain substantially constant the volumetric flow through said outlet and a controller subject to external working conditionsvconnected with opposite sides of said main diaphragm.

3.'A gas valve according to claim 1 and comprising a spring operating on said valve member against the gas pressure on the outer side of said shroud and a capsule removably vmounted in said shroud and containing said valve member and spring.

4. A gas valve according to claim 1 and further characterized by a capsule removablymounted in said shroud, said valve member being mounted in said capsule and a spring disposed between the base of said capsule and said valve member, and said valve member having projections thereon in order to reduce the area of its contact with the base surface of said capsule.

5. A gas valve according to claim 1 and comprising a, double-walled casing member inset in said main casing enclosing said diaphragm, one wall of said 4casing member constituting said main division plate and having an opening therein forming said control passage, a capsule having a base provided with a bored stem removably mounted in said shroud to dispose said stem in said opening and a control valve in said capsule adapted to control said opening in the division` plate.

6. A diaphragm-operated gas valve comprising a main casing having a gasv inlet and a gas outlet at one end thereof, a main division plate in said casing having a control passage there through, a main diaphragm on the side of the division plate opposite said gas inlet and said' gas outlet, a main valve on the other side of said division plate controlling said outlet, a connection Abetween the diaphragm and the valve, a shroud enclosingsaid main valve 'and the outlet openying and having an opening therein, a manually adjustable valve member controlling said opening in said. shroud and thereby governingvthe pressure 'diierenceon opposite sides of said 7g a valve chamber in said shroud disposed over said control passage and removed from said opening in said shroud, a valve member within said chamber intermediate its top and bottom, said chamber having an opening at its top through said shroud and an opening in its bottom communicating with said control passage through said main division plate and with the interior of said shroud so as to subject said valve member to the pressures on opposite sides of the shroud for -controlling said control passage and for influencing the diaphragm to maintain substantially constant the volumetric flow through said outlet, gas-conduit means connecting opposite sides of said diaphragm, and a pressure-relief valve having a controller member subject to external working conditions connected with the side of said main diaphragm opposite said main division plate.

7. A gas valve according to claim 6 and comprising a toothed r" .1g on said manually adjustble valve member, a toothed wheel engaging said ring and a spindle connected to the wheel for manually adjusting said valve member.

8. A gas valve according to claim l further comprising a slide valve member as the valve for said opening in the shroud and a set screw for adjustment of said slide valve member accessible through an opening in the valve casing and a removable plug for closing said opening in the valve casing.

9. A diaphragm-operated gas valve comprising a casing having a-gas inlet and a gas outlet at one end thereof, a main division plate in said easing having a control passage therethrough, a main diaphragm on the side of said division plate opposite said inlet and outlet openings, a main valve on the other side ofsaid division plate controlling said outlet, a connection between the diaphragm and the valve, a shroud enclosing said main valve and the outlet opening and having a valve-controlled opening therein, a valve member within said shroud and subject to the pressures on opposite sides of the shroud for controlling said control passage and for inuencing the diaphragm to maintain substantially constant the volumetric flow through said outlet, a gas conduit connecting the opposite sides of the diaphragm for the flow of gas from the side of said diaphragm facing said main division plate to the opposite side of said diaphragm, a throttling restriction interposed in said gas conduit, a pressure-relief valve connected to said gas conduit on the outiow side of said throttling restriction and a controller member for said pressure-relief valve subject to external working conditions.

10. 'A gas heating plant and control system therefor comprising a container of a uid medium to be heated having a supply inlet and a discharge outlet, a main gas burner, a gas supply for said burner, a main gas valve having an inlet side connected to said gas supply and an outlet side connected to saidv main gas burner, means comprising a diaphragm so controlling said main gas valve as to maintain said valve in closed position when the gas pressures are approximately the same on opposite faces of the diaphragm and operable by differences in gas pressure on the opposite faces of said diaphragm to effect degrees of opening movement of said main gas valve corresponding to differences in gas pressure on opposite faces of said diaphragm, conduit means fed with gas from said gas supply and connected to opposite sides of lsaid diaphragm.

to produce gas pressures thereagainst, gaspressure-control valve connected with said conduit means and operating in response to changes in the working conditions of said uid medium in the plant to determine the time Aof opening and closing of said main gas valve, and means operating in response to variations in pressure in the main gas flow when said main gas valve is open to so vary the differential pressures on said diaphragm as to decrease the extent of opening movement of 'said main gas valve upon increase in pressure in the main gas iiow above a predetermined pressure and to increase the extent of opening movement of said main gas valve upon decrease in pressure in the main gas flow below said predetermined pressure; v

11. A gas heating plant and control system therefor comprising a container of a fluid medium to be heated having a supply inlet and a discharge outlet, a ina-1n gas burner, a main gas pipe, a valve casing having an inlet connected to said pipe and an outlet passage connected to said main gas burner, a main gas valve for said outlet passage, means comprising a diaphragm so controlling said main gas valve as to maintain said valve in closed position when the gas pressures are approximately the same on opposite faces of said diaphragm and operable by differences in gas pressure ontheopposite faces of said diaphragm to effect degrees of opening movement of said main gas valve corresponding to differences in gas pressure on opposite faces of said diaphragm, 'conduit means fed with gas from said main gas pipe and connected to opposite sides of said diaphragm to produce gas pressures thereagainst, a gas-pressure-control valve connected with said conduit means and operating in response to changes in the working conditions of said iiuid medium in the plant to determine the time of opening and closing of said main gas valve, and means so operating in response to variations in the gas pressure in said outlet passage on the outlet side of said main gas valve when said main gas valve has been opened by said gas-pressure-control valve as to decrease the extent of opening movement of said main gas valve upon increase in gas pressure in said outlet passage above a predetermined pressure and to increase the extent of opening movement of said main gas valve upon decrease in gas pressure in said outlet passage below a predetermined pressure.

12. A gas heating plant and control system therefor comprising a container of a uid medium .to be heated having a supply inlet and a discharge outlet, a main gas burner, a gas supply for said burner, a diaphragm-operated main gas valve for said gas supply having a diaphragm adapted to be actuated by differential pressures, means'comprising a control-gas conduit supplied with gas from said gas supply and connected to opposite sides of said diaphragm and a control valve connected with said control-gas conduit and operating in response to changes in the working conditions of said fluid medium in the plant to control the time of opening and closing of said main gas valve, and additional control-means comprising a valve connected with said control-gas conduit and actuated by the main gas flow when said main gas valve is open to so control the diierential pressures on said diaphragm and thereby the extent of opening of said main gas valve as to maintain the ow of gas to said main gas burner substantially at a volumetric constant.

13. A gas heating plant and control system therefor comprising a container of a fluid me dium to be heated having a supply inlet and a discharge outlet, a main gas burner, amain gas pipe, a valve casing having an inlet connected to said pipe and an outlet passage connected to said main gas burner, a diaphragm-operated main gas valve for said outlet passage having a diaphragm adapted to be actuated by diierential pressures, means comprising a control-gas conduit supplied with gas from said main gas pipe and connected to opposite sides of said diaphragm and a control valve connected with said controlgas conduit and operating in response to changes in the working conditions of said fluid medium in the plant to control the time of opening and closing of said main gas valve and additional control means comprising a pressure-controlled valve connected to one side of said diaphragmV and having a pressure-controlled member exposed to and actuated by the gas pressure in said outlet passage on the outlet side of said main gas valve to so control the differential pressures on said diaphragm and thereby the extent of opening of said main gas valve as to maintain the gas pressure in said outlet passage on the outlet side of said valve substantially constant.

14. A regulator for the gas supply to a hot water device comprising a main gas burner, a gas supply for said burner, a valve-controlled water pipe, a diaphragm-controlled main gas valve for said gas supply having a diaphragm element operable by differences in gas pressure on its opposite faces to effect degrees of opening movement of said valve corresponding to differences in gas pressure on opposite faces of said diaphragm element, conduit means fed with gas from said gas supplyand connected to opposite sides oi' said diaphragm element to produce gas pressures thereon, a control valve connected with said conduit means and operable by ilow of water in said water pipe to establish a difference in gas pressure on opposite faces of said diaphragm element effective in opening said main gas valve and an additional control valve connected with said conduit means and actuated by the main gas flow when said main gas valve is open to so control the differential pressures on said diaphragm element as to maintain the ilow of gas to said main gas burner substantially at a volumetric constant.

15. A diaphragm-operated gas valve comprising a main gas supply conduit, a main gas valve for said conduit and a diaphragm-.mechanically connected thereto and adapted to be actuated by differential-pressures on its opposite sides to open said main gas valvewsaid main gas valve closing when the pressures are substantiallyequalized on opposite sides of said diaphragm, means compris- .ing a control-gas conduit fed with gas from said main gas supply conduit and connecting opposite sides of said diaphragm and a thermostatically controlled pilot-lighter valve connected to said control-gas conduit automatically operating to es-. tablish substantially' equal gas pressures on opposite sides of said diaphragm so as to cause said main gas valve to close when said pilot-lighter valve is closed and to establish differential pressures on said diaphragm when said pilot valve is open so as to cause-said diaphragm to open said main-gas valve, and means comprising a pressure actuated valve connected with said control-gas conduit and actuated by the maingas flow when saidmain `gas valve is open to so control the differential pressures on said diaphragm and thereby the extent of opening oi' said main-gas valve as to maintain the flow' of gas through said main-gas valve substantially at a volumetric constant.

16. A diaphragm-operated valve vfor a gas burner comprising the combination with a main gas burner and a gas supply, of a main gas valve between said supply and said burner, a diaphragm mechanically connected to said valve and adapted to beactuated by diierential pressure thereon to open said valve, means comprising a control-gas conduit connecting opposite sides of said diaphragm and fed with gas from said gas supply and a pilot-lighter valve connected to said control-gas conduit automatically operating to establish such gas pressures on opposite faces of said diaphragm as to close said main gas valve when the pilot flame is extinguished, and means comprising a` pressure-actuated valve exposed to and actuated bythe main gas flow on the supply side of said gas-control conduit and connected with said conduit in series with said lighter-burner valve between the latter and said gas supply and automatically operating in response to changes in pressure of said main gas ilow when said main gas valve is open to so control the differential pressures on said diaphragm and thereby the extent of opening of `said main gas valve as to maintain the flow of gas through said main gas valve substantially at a volumetric constant.

17. A gas heating -plant and control system therefor comprising a container of a fluid medium to be heated having a supply inlet and a discharge outlet, a gas supply, a main gas burner, a diaphragm-operated gas valve between said gas supply and 4said main burner having a diaphragm adapted to be actuated by differential pressures on its opposite faces to open said main gas valve, gas-conduit-means connecting opposite sides o1' said diaphragm and fed with gas from said gas supply, a pilot burner connected to said gas-conduit-means and a pilot-lighter valve closing when the pilot flame is extinguished and establishing through said gas-conduit-means such pressures on said diaphragm as to close said main gas valve, a controller valve connected to said gasconduit-means in series with said pilot-lighter valve, actuating mechanism for said controller valve automatically operating to open and close said controller valve in response to changes in the working conditions of said uid medium in the plant when said pilot-lighter valve is open and thereby to establish through said gas-conduit means such pressures on saidk diaphragm as to control the time of opening-and closing of said main gas valve, and additional control means comprising a valve connected tosaid gas-conduitmeans in series with said pilot-lighter valve and said controller valve and actuated by the main gas ilow when said main gas vlve is open to so control the diil'erential pressures on-said diaphragm as to maintain the main gas flow through -said main gas valve substantially at avolumetric constant.

18. A diaphragm-operated gas valve comprising a main-valve casing having a gas inlet and a gas outlet, a main gas valve in said casing controllingthe connection between said inlet and said outlet, a diaphragm casing and a diaphragm therein dividing said diaphragm casing into chambers on opposite sides of the diaphragm, a

`to open Vsaid main gas valve and said main gas valve -closes when the pressures areapproxi- .connection between said diaphragm and said 70 mately equalized in said 'chambers on opposite 1I sides'of said diaphragm, conduit means connecting' one of said chambers with said main-valve casing so as to feed gas from said main-valve casing to said one chamber, conduit means connecting said one chamber with the other of said chambers on the opposite side of said diaphragm for the iiowof gas from said onechamber to said other chamber, a pressure-relief valve connected to said other chamber and functioning in the open position to produce a diiferential pressure in said chambers on the opposite faces of said diaphragm leffective in opening said main-gas valve, and a valve in said main-valve casing separate from said lmain-gas valve` automatically operating under the pressure of -the main gas flow in said main-,valve casingv when said main-gas valve is open to so control the feed ofgas intol 'at a volumetric constant.

19. A diaphragm-operated gas valve comprising a casing and a-diaphragm therein, said casing being formed with interior walls cooperating with said diaphragm to form chambers on opposite sides of said diaphragm with said diaphragm as the common wall between them, a main-gas inlet to and a maingas outlet from said casing on one side of said diaphragm,.a main-gasl valve for said outlet operatively connected to said diaphragm, said diaphragm operating by differential pressures onits opposite faces to open said maingas valve and said main-gas valve automatically closing when the pressures are approximately the same on the opposite faces of said diaphragm, one of said chambers being connected to said main-gas inlet for feeding gas to said one chamber, conduit means connectingsaid one chamber with the other of said chambers on the opposite side of said diaphragm for the flow of gas from said one chamber to said other chamber, a pressure-relief valve connected to said other chamber and -functioning in the open position to produce differential pressure on the opposite faces of said diaphragm eifective in opening said main-gas valve, a pressure-control valve in the connection between said pressure-relief valve and said other chamber and means for operating said pressure-control valve comprising Va pressureoperated member subject to the gas pressure in said gas outlet and automatically operating in response to changes in said gas pressure above and below a predetermined pressure.

20. A diaphragm-operated gas valve comprising a casing having amain gas inlet opening and a main gas outlet opening, a main gas valve controlling said outlet opening, a diaphragm in said casing adapted to be operated by differential pressures on its opposite sides, saiddiaphragm having one side exposed to -the pressure of the Y means in said"casing forming with said diaphragm a pressure-control chamber on the opposite or low-pressure side of said diaphragm, said diaphragm being connected with the main valve to cause displacement of the same, a

.thermostatic pilot lighter valve. automatically 4connecting the lighter valve with the low pressure side of said diaphragm, and a controller valve arranged in the conduit connecting the lighter valve with the low pressure side of said diaphragm and means for operating said controller valve comprising an actuating member influenced by the gas pressure flowing through said outlet opening for influencing the diaphragm and main gas valve to maintain substantially constant the gas pressure in said outlet opening.

21. A diaphragm-operated gas valve compris-.

ing a casing having a main gas inlet opening and a main gas outlet opening, a vmain gas valve controlling said outlet opening, a diaphragm in said casing adapted to be operated by dierential pressures on its opposite sides, and'wall means gin said casing forming with said diaphragm pressure chambers on'the opposite sides of said diaphragm functioning' as high and low-pressure sides, said diaphragm being connected with the main valve to cause displacement of the same, a thermostatic pilot lighter valve adapted to close when the lighter ame-is extinguished, a conduit connecting the lighter valve with the high pressure side of said diaphragm, a conduit connect- Ving the lighter valve with the low pressure side of said diaphragm, conduit means feeding gas from said main gas inlet tothe high pressure side of said diaphragm and a controller valve for said conduit means actuated by the main gas ow in said casing when said main gas valve is open to influence said diaphragm and thereby the main valve to maintain substantially constant the volumetric rate of gas ow through said outlet opening.

2 2. A gas Valve according to claim 20 and further characterized by said actuating member comprising an auxiliary diaphragm connected to said controller valve and subject on one side to the gas pressure on the outlet side of the main gas valve.

23. A gas valve according to claim 2O and in which said actuating member comprises an auxiliary diaphragm connected to said controller valve and subject on one side to the gaspressure on the outlet side of said main gas valve and subject on its other side to atmospheric pressure and the action -of a spring.

GEORG HEGWEIN. FRIEDRICH WILHELM STOCKMEYER. CURT STEINHARDT.

WILHELM RMMELT.

ALBERT scm/Im.

OTTO WURST. 

